Point clouds in blender
I don't think you need an add-on for what you want to do, there are a lot of tools for viewing efficiency.

Hide the selection, H key, undo Alt+H
View only the selected objects, / key, undo / (toggle)
Crop the view to a border, Alt+B and define a border left click + drag, undo Alt+B

Perhaps the third is what is suitable in your case.